[go: up one dir, main page]

US2664618A - Electrical contact - Google Patents

Electrical contact Download PDF

Info

Publication number
US2664618A
US2664618A US532377A US53237744A US2664618A US 2664618 A US2664618 A US 2664618A US 532377 A US532377 A US 532377A US 53237744 A US53237744 A US 53237744A US 2664618 A US2664618 A US 2664618A
Authority
US
United States
Prior art keywords
silver
contact
electrical contact
weight
electrical
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US532377A
Inventor
John D Kleis
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Fansteel Inc
Original Assignee
Fansteel Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Fansteel Inc filed Critical Fansteel Inc
Priority to US532377A priority Critical patent/US2664618A/en
Application granted granted Critical
Publication of US2664618A publication Critical patent/US2664618A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Classifications

    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H1/00Contacts
    • H01H1/02Contacts characterised by the material thereof
    • H01H1/021Composite material
    • H01H1/023Composite material having a noble metal as the basic material
    • H01H1/0237Composite material having a noble metal as the basic material and containing oxides
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S428/00Stock material or miscellaneous articles
    • Y10S428/922Static electricity metal bleed-off metallic stock
    • Y10S428/9265Special properties
    • Y10S428/929Electrical contact feature
    • YGENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10TECHNICAL SUBJECTS COVERED BY FORMER USPC
    • Y10STECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y10S75/00Specialized metallurgical processes, compositions for use therein, consolidated metal powder compositions, and loose metal particulate mixtures
    • Y10S75/95Consolidated metal powder compositions of >95% theoretical density, e.g. wrought
    • Y10S75/951Oxide containing, e.g. dispersion strengthened

Definitions

  • This invention relates to electrical contacts, particularly, contacts used in apparatus wherein the contact pressure is fairly high.
  • One of the objects of this invention is toprovide electrical contacts having :a relatively high resistance to welding and transfer.
  • Another object of this invention is to provide electrical contacts having a relatively constant contact resistance.
  • a further object of this invention is to provide electrical contacts formed of a composition consisting of a major portion of silver and which has a much higher resistance to electrical errosion than contacts formed of silver.
  • the present invention contemplates the addition of from the lowest useful amounts up to about 50% molybdenum oxide to silver and silverbase alloys.
  • Molybdenum oxide increases appreciably the contact resistance of silver and silver-base alloys; however, the increase is not objectionable where the contact pressure is relatively high. Although the contact resistance is somewhat higher, I have found that the presence of molybdenum oxide serves to maintain the contact resistance relatively constant throughout the life of the contacts. Compositions containing molybdenum oxide have a very high resistance to welding and an exceptionally low transfer tendency.
  • a further improvement in the wear resistance and hardness of the composition may be efl'ected by adding small amounts of nickel, for example up to about 5%. Substantially large amounts are not desired since such amounts would increase appreciably the electrical resistance of the composition and substantially increase the electrical errosion due to excessive arcing.
  • the carbon may be use-d very small amounts, i have found'that "the small amounts are very effective in lowering the con tact resistance of the compositions and in stabilizing the contact resistance.
  • I may employ copper, nickel or carbon or mixtures of two of the substances or all three of these substances in producing compositions having the desired mechanical properties.
  • compositions contemplated by the present invention are well suited for use in apparatus such as relays, switches, circuit breakers and the like, wherein an appreciable contact pressure is used and where the contacts are normally closed.
  • the contacts are prepared according to well-known powder metallurgy methods. In those instances where small amounts of nickel and copper are employed, the nickel or copper may be first alloyed with silver and the resulting product finely comminuted and mixed with the molybdenum oxide. The resulting mixture is molded or pressed to form the compact which is then sintered at an appropriate temperature to form a substantially solid body.
  • the compositions are preferably sintered in a neutral atmosphere but may be sintered under a vacuum, if desired. A slight reduction of the molybdenum oxide may occur if a reducing atmosphere is used in the sintered operation; however, a slight reduction of the oxide to molybdenum will not afiect adversely the properties of the compositions.
  • An electrical contact suitable for use in apparatus such as relays, switches, circuit breakers and the like, wherein an appreciable contact pressure is used, said contact having an electrical contact surface and being made of a compacted, sintered and non-porous composition consisting of silver, molybdenum oxide in an amount up to about 50% by weight of the silver, and from 0 to about 5% by Weight each of copper, nickel and carbon, based on the weight of the contact composition.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Composite Materials (AREA)
  • Materials Engineering (AREA)
  • Contacts (AREA)

Description

Patented Jan. 5, 1954 UNETED steel Metallurgical:Crporation, NorthGhica'go, Ill., acorporat'ion of New York No Drawing. Application April 22-, 1944,
. Serial No. 532,377
4 Claims. 1
This invention relates to electrical contacts, particularly, contacts used in apparatus wherein the contact pressure is fairly high.
One of the objects of this invention is toprovide electrical contacts having :a relatively high resistance to welding and transfer.
Another object of this invention is to provide electrical contacts having a relatively constant contact resistance.
A further object of this invention is to provide electrical contacts formed of a composition consisting of a major portion of silver and which has a much higher resistance to electrical errosion than contacts formed of silver.
Other objects and advantages of this invention will become apparent from a consideration of the description and claims which follow.
The present invention contemplates the addition of from the lowest useful amounts up to about 50% molybdenum oxide to silver and silverbase alloys.
The desirable improvements in electrical contact characteristics are also effected by the incorportion of like amounts of molybdenum oxide in alloys of silver with other metals such as gold and the platinum group metals.
Molybdenum oxide increases appreciably the contact resistance of silver and silver-base alloys; however, the increase is not objectionable where the contact pressure is relatively high. Although the contact resistance is somewhat higher, I have found that the presence of molybdenum oxide serves to maintain the contact resistance relatively constant throughout the life of the contacts. Compositions containing molybdenum oxide have a very high resistance to welding and an exceptionally low transfer tendency.
Small amounts of copper, that is up to about 5% by weight of the composition, may be added to improve the resistance of the contacts to mechanical wear and to harden the composition. Large amounts of copper are not desired since such amounts reduce the melting point of the silver, thereby greatly increasing the tendency of the contacts to weld, arc and erode.
A further improvement in the wear resistance and hardness of the composition may be efl'ected by adding small amounts of nickel, for example up to about 5%. Substantially large amounts are not desired since such amounts would increase appreciably the electrical resistance of the composition and substantially increase the electrical errosion due to excessive arcing.
Small proportions of carbon,
for example up to about 5%,
may be added to improve the wear re'esistanc'e of the composition -and substantially improve the non welding pro erties ofthe com= position. Although the carbon may be use-d very small amounts, i have found'that "the small amounts are very effective in lowering the con tact resistance of the compositions and in stabilizing the contact resistance.
In the preparation of the compositions of this invention, I may employ copper, nickel or carbon or mixtures of two of the substances or all three of these substances in producing compositions having the desired mechanical properties.
Electrical contacts prepared from compositions contemplated by the present invention are well suited for use in apparatus such as relays, switches, circuit breakers and the like, wherein an appreciable contact pressure is used and where the contacts are normally closed. The contacts are prepared according to well-known powder metallurgy methods. In those instances where small amounts of nickel and copper are employed, the nickel or copper may be first alloyed with silver and the resulting product finely comminuted and mixed with the molybdenum oxide. The resulting mixture is molded or pressed to form the compact which is then sintered at an appropriate temperature to form a substantially solid body. The compositions are preferably sintered in a neutral atmosphere but may be sintered under a vacuum, if desired. A slight reduction of the molybdenum oxide may occur if a reducing atmosphere is used in the sintered operation; however, a slight reduction of the oxide to molybdenum will not afiect adversely the properties of the compositions.
I claim:
1. An electrical contact suitable for use in apparatus such as relays, switches, circuit breakers and the like, wherein an appreciable contact pressure is used, said contact having an electrical contact surface and being made of a compacted, sintered and non-porous composition containing silver, molybdenum oxide in an amount up to about 50% by Weight of the silver, and carbon in an amount up to about 5% by weight of the contact composition.
2. An electrical contact suitable for use in apparatus such as relays, switches, circuit breakers and the like, wherein an appreciable contact pressure is used, said contact having an electrical contact surface and being made of a compacted, sintered and non-porous composition consisting of silver, molybdenum oxide in an amount up to about 50% by weight of the silver, and from 0 to about 5% by Weight each of copper, nickel and carbon, based on the weight of the contact composition.
3. An electrical contact suitable for use in apparatus such as relays, switches, circuit breakers and the like, wherein an appreciable contact pressure is used, having an electrical contact surface, said contact being made of a compacted, sintered and non-porous composition containing an electrical contact material of the class consisting of silver and a silver base alloy electrical contact material consisting of silver and a noble 7 metal selected from the class consisting of gold and platinum, from to about by Weight each of copper, nickel and carbon, based on the weight of the contact composition, and molybdenum oxide in an amount up to about 50% by weight of the said silver or silver base alloy contact material.
4. An electrical contact suitable for use in apparatus such as relays, switches, circuit breakers and the like, wherein an appreciable contact pressure is used, said contact having an electrical contact surface and being made of a compacted, sintered and non-porous composition containing an electrical contact material of the class con- 4 sisting of silver and a silver base alloy electrical contact material consisting of silver and a noble metal selected from the class consisting of gold and platinum, molybdenum oxide in an amount up to about by weight of the said silver or silver base alloy contact material, and carbon in an amount up to about 5% by weight of the contact composition.
JOHN D. KLEIS.
References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 1,937,381 Bond et a1. Nov. 28, 1933 1,986,210 Maas Jan. 1, 1934 2,005,645 Bond et a1 June 18, 1935 2,057,604 Zickrick Oct. 13, 1936 2,145,690 Hensel Jan. 31, 1939 2,151,905 Emmert Mar. 28, 1939 2,200,854 Ruben May 14, 1940 2,200,855 Ruben May 14, 1940 2,255,120 Kiefer Sept. 9, 1941 2,394,501 Weiller Feb. 5, 1946 2,396,101
Hensel et a1 Mar. 5, 1946

Claims (1)

1. AN ELECTRICAL CONTACT SUITABLE FOR USE IN APPARATUS SUCH AS RELAYS SWITCHES, CIRCUIT BREAKERS AND THE LIKE, WHEREIN AN APRECIABLE CONTACT PRESSURE IS USED, SAID CONTACT HAVING AN ELECTRICAL CONTACT SURFACE AND BEING MADE OF A COMPACTED, SINTERED AND NON-POROUS COMPOSITION CONTAINING SILVER, MOLYBDENUM OXIDE IN AN AMOUNT UP TO ABOUT 50% BY WEIGHT OF THE SILVER, AND CARBON IN AN AMOUNT UP TO ABOUT 5% BY WEIGHT OF THE CONTACT COMPOSITION.
US532377A 1944-04-22 1944-04-22 Electrical contact Expired - Lifetime US2664618A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
US532377A US2664618A (en) 1944-04-22 1944-04-22 Electrical contact

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US532377A US2664618A (en) 1944-04-22 1944-04-22 Electrical contact

Publications (1)

Publication Number Publication Date
US2664618A true US2664618A (en) 1954-01-05

Family

ID=24121521

Family Applications (1)

Application Number Title Priority Date Filing Date
US532377A Expired - Lifetime US2664618A (en) 1944-04-22 1944-04-22 Electrical contact

Country Status (1)

Country Link
US (1) US2664618A (en)

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2818633A (en) * 1955-03-02 1958-01-07 Gibson Electric Company Electrical contact
US3045332A (en) * 1955-01-28 1962-07-24 Gen Electric Bonding member
US3841869A (en) * 1970-10-21 1974-10-15 Square D Co Method of making light-duty electrical contacts composed of silver and ruthenium dioxide
US4859238A (en) * 1987-06-06 1989-08-22 Degussa Aktiengesellschaft Silver-iron material for electrical contacts
US6001149A (en) * 1996-01-26 1999-12-14 Siemens Aktiengesellschaft Process for producing a shaped article from contact material based on silver, contact material and shaped article
WO2007041431A1 (en) * 2005-10-03 2007-04-12 Analog Devices, Inc. Mems switch contact system
US20080151464A1 (en) * 2006-12-22 2008-06-26 Analog Devices, Inc. Method and Apparatus for Driving a Switch
US20100068854A1 (en) * 2005-10-03 2010-03-18 Analog Devices, Inc. MEMS Switch Capping and Passivation Method

Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1937381A (en) * 1930-04-15 1933-11-28 Du Pont Oxidation catalyst
US1986210A (en) * 1934-04-20 1935-01-01 Albert W Langkau Copper alloy for conducting electricity
US2005645A (en) * 1930-04-15 1935-06-18 Du Pont Process of oxidizing aliphatic alcohols to aldehydes
US2057604A (en) * 1934-05-23 1936-10-13 Gen Electric Electrical switch contact
US2145690A (en) * 1937-09-24 1939-01-31 Mallory & Co Inc P R Electric contact material
US2151905A (en) * 1937-09-29 1939-03-28 Mallory & Co Inc P R Electric contact combination
US2200855A (en) * 1939-05-02 1940-05-14 Ruben Samuel Electrical contact
US2200854A (en) * 1939-05-02 1940-05-14 Ruben Samuel Electrical contact
US2255120A (en) * 1939-10-13 1941-09-09 Stackpole Carbon Co Weldable silver-graphite contact and method of making it
US2394501A (en) * 1942-09-12 1946-02-05 Square D Co Electrical contact
US2396101A (en) * 1942-10-23 1946-03-05 Mallory & Co Inc P R Electrical contact

Patent Citations (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1937381A (en) * 1930-04-15 1933-11-28 Du Pont Oxidation catalyst
US2005645A (en) * 1930-04-15 1935-06-18 Du Pont Process of oxidizing aliphatic alcohols to aldehydes
US1986210A (en) * 1934-04-20 1935-01-01 Albert W Langkau Copper alloy for conducting electricity
US2057604A (en) * 1934-05-23 1936-10-13 Gen Electric Electrical switch contact
US2145690A (en) * 1937-09-24 1939-01-31 Mallory & Co Inc P R Electric contact material
US2151905A (en) * 1937-09-29 1939-03-28 Mallory & Co Inc P R Electric contact combination
US2200855A (en) * 1939-05-02 1940-05-14 Ruben Samuel Electrical contact
US2200854A (en) * 1939-05-02 1940-05-14 Ruben Samuel Electrical contact
US2255120A (en) * 1939-10-13 1941-09-09 Stackpole Carbon Co Weldable silver-graphite contact and method of making it
US2394501A (en) * 1942-09-12 1946-02-05 Square D Co Electrical contact
US2396101A (en) * 1942-10-23 1946-03-05 Mallory & Co Inc P R Electrical contact

Cited By (11)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3045332A (en) * 1955-01-28 1962-07-24 Gen Electric Bonding member
US2818633A (en) * 1955-03-02 1958-01-07 Gibson Electric Company Electrical contact
US3841869A (en) * 1970-10-21 1974-10-15 Square D Co Method of making light-duty electrical contacts composed of silver and ruthenium dioxide
US4859238A (en) * 1987-06-06 1989-08-22 Degussa Aktiengesellschaft Silver-iron material for electrical contacts
US6001149A (en) * 1996-01-26 1999-12-14 Siemens Aktiengesellschaft Process for producing a shaped article from contact material based on silver, contact material and shaped article
WO2007041431A1 (en) * 2005-10-03 2007-04-12 Analog Devices, Inc. Mems switch contact system
US20070115082A1 (en) * 2005-10-03 2007-05-24 Analog Devices, Inc. MEMS Switch Contact System
US20100068854A1 (en) * 2005-10-03 2010-03-18 Analog Devices, Inc. MEMS Switch Capping and Passivation Method
US7968364B2 (en) 2005-10-03 2011-06-28 Analog Devices, Inc. MEMS switch capping and passivation method
US20080151464A1 (en) * 2006-12-22 2008-06-26 Analog Devices, Inc. Method and Apparatus for Driving a Switch
US8194382B2 (en) 2006-12-22 2012-06-05 Analog Devices, Inc. Method and apparatus for driving a switch

Similar Documents

Publication Publication Date Title
US4162160A (en) Electrical contact material and method for making the same
US2470034A (en) Electric contact formed of a ruthenium composition
US2145690A (en) Electric contact material
US2983996A (en) Copper-tungsten-molybdenum contact materials
US2664618A (en) Electrical contact
JP3280968B2 (en) Silver-based contact material for use in switches in the power industry and a method for producing contact pieces from this material
JPH0377265B2 (en)
US2394501A (en) Electrical contact
US2195307A (en) Contact
US3827883A (en) Electrical contact material
US3045331A (en) Electrical contacts of high arc erosion resistance and method of making the same
US2180826A (en) Electric contact
US2818633A (en) Electrical contact
US1984203A (en) Hard metallic composition and contacts thereof
US3272603A (en) Refractory metal composite
US2199458A (en) Electric contact
US2221286A (en) Electric contact
US3669634A (en) Metal composites
US2202054A (en) Electric contact element
US2200854A (en) Electrical contact
US2247754A (en) Electric contact
US3225169A (en) Silver-refractory metal electrical contact having refractory metal carbide in the marginal layer of its active contact face
JPS63118032A (en) Contact materials for vacuum shields and disconnectors
JPH0768593B2 (en) Sintered contact material for low voltage switchgear for electric power
US2396100A (en) Electric contact